Valve-operating mechanism



F. H. WELLS.

VALVE OPERATING MECHANISM. APPLICATION flLED JULY 31. 1920.

1,410,787. Patented Mar. 28, 1922.

I 7 g) 5 Is A a w Z 2 I! I 4* I 4' w 1' ll '7 w :7 5 Is '6 INVENTOR ATTORNEYS V a citizen of :i E STATES ATENT' oFFIeEQ FREDERIGK HQWELLS, OF BOONTON, NEW JERSEY.

VALVE-OPERATING MECHANISM.

, is a clear, fiilhand exact description.

This invention relates to valves and par-,

ticularly to the operating mechanism for. valves of internal combustionengmes, such as are usedin automobiles, and an object of my invention isto provide an improved,

valve operating structure whichwill admit of reductionin weight of the parts and at the same timemaintain a high efficiency at high speeds of motor operation 1 i In constructions using springs for 010s ing the valves, an engine speed is eventually reached at which the force necessaryto accelerate the valves sufliciently "to, compel them to follow the cam which opens the valve becomes greater than the available force of the spring, which results in the valve lagging during the closing operation thereof, unless very heavy springs are employed, which are of course objectionable. This lagging tendency, too, becomes more marked as the spring ages. When heavy springs are used, heavier stresses are thrown upon the valve operating gear, resulting in waste of horsepower used in the engine.

To overcome some of these difficulties, it has been proposed to use very light parts or to give to the valves a very small lift. Even in such constructions, however, comparatively heavy springs are necessitated and this method is further open to the objection that a relatively small valve opening reduces the engine efliciency; and furthermore, light parts are objectionable on account of a tendency to breakage and distortion due to the excessive heat to which the valves are subjected.

My present invention overcomes the difficulties heretofore experienced, and enables the use of parts having adequate weight without sacrificing efiiciency.

A feature of my invention consists in the provision of valve operating mechanism controlling positively both the opening and closing of, the valves.

A further feature of my invention consists of the provision of resilient means for effecting the final seating of a valve, which re- Specification of Letters Patent. Patented R131. 28, 1922.

1920. Serial no. 400,484.

silient means is engaged, by the positive valve closingmeans near the end of its valve closing movement.

Other features and advantages will become apparent from the followingdetailed description and claims when taken in 0011- nection with the accompanyingdrawings in which Fig.1 is a vertical section of the valve.

closing mechanism; and v Fig. 2, a similar section at right angles thereto. f

Referring to the drawings, 1 indicates the usual valve operating shaft, suitably connected so as to be driven from the engine, and on this shaft are mounted cams 2 and a cam 3 located intermediate between the cams 2; The cams 2 are the valve closing cams, whilejthe cam 3 is designed to open the valve or valves, and for this purpose cams 2 each engage a roller 4: suitably journaled on a crosspiece 5 forming the top member of a stirrup consisting of U-shaped members 6, said members having a lower member 7, Fig. 1, in which is journaled a roller 8, against which cam 3 bears for the purpose of opening the valves, the valves in the present construction pening downwardly. The U- shaped members are secured to the top member 5 of the stirrup by bolts or other suitable fastening devices 9, and to the lower member 7 of the stirrup by means of bolts or other fastening devices 10. The stirrup is guided, in its up and down movement under action of the cams, by projections 11 and 12, the upper projection 11 having a bearing 18 in a suitable frame piece, the projection 12 having a similar bearing 14: in the same frame.

The stems of the valves themselves are indicated at 15 and are connected to the stirrup by resilient means and for this purpose I prefer to use laminated springs indicated at 16. The valve stems are each shouldered and the spring is fastened to the stem of each by means of nuts 17 engaging a threaded end of the stem, and when screwed down securely clamping the laminated spring to the valve stem. The member 7 of the stirrup is shouldered at 18, the laminated spring having a hole therethrough near the center thereof of such size that the spring engages the shoulder 18 and is clamped to the member 7 by the nut 19 engaging a screw thread- V final seating.

id portion of the member 7, as shown in The cams 2 are of such form that during the closing operation of the valves, and preferably near the end of the cam stroke to close the valves, the laminated spring is put under tension, which tension acts to give .a

A very slight excess movement of the cams 2 is all that is necessary to accomplish this, and such movement may not be more than one-hundredth of an inch.

The action of the cams on the rollers tends to prevent the stirrup from turning about its vertical axis and to further guard against any possibility of turning, the hole in the laminated spring may be made polygonal in shape, and the shankof the member 7 may be shaped correspondingly.

The laminated spring is made quite stiff so that ordinarily it acts merely as a connecting means between the frame or stirrup and .the valves, to move them; The final movement, however, of the frame in closing the valves, acts to stress sa1d sprlng so as to cause a final seating of the valves under spring pressure.

"lVhile I have describedand shown a preferred embodiment of my invention, it is understood that variations may be resorted to without departing from the spirit of the invention as defined by the claims.

Having thus described my invention what I claim and desire to secure by Lettersnecting both valves andstressed by said closing means during the final portion of its valve closing movement, said resilient means acting to seat both valves;

3. In a valve structure, the combination with a plurality of valves, a frame, a lami- J nated spring connecting said frame and valves, and means for "positively reciprocating said frame. 7 V r a 4:. In a valve structure, the combination with a plurality of valves, of a frame, a laminated spring connecting said frame and frame to open and close said valves, the partsv valves, means for positively moving said being so constructed andarranged that the" positive means acts to put said laminated spring under stress as the positive means -moves to positionfto close said valves. H

Signed at New York, N. this 28thday" I of July, 1920.

FREDERICK H. WEL S: 

